This invention relates to the field of seismic data interpretation and, more particularly, to the processing of databases of well log and geophone-obtained seismic information to better assist interpreters in classifying subsurface formations.
The subject matter of the present invention relates to a method and apparatus for generating a cross plot in attribute space in response to a plurality of attribute data and then generating a classified result or “class data set” based on the data alignment in the crossplot. More particularly, the subject matter of the present invention relates to an apparatus and associated method including a computer workstation having a novel software package stored therein, the workstation having a display screen for displaying a novel classified result, known as a class data set, for viewing by a workstation operator. The class data set is generated and displayed on the display screen when the workstation processor executes the novel software package. When the novel software package is executed, a crossplot in attribute space is generated in response to a plurality of different attribute data obtained in response to a seismic operation, and the class data set is generated in response to the crossplot.
In the oil industry, well log data (obtained from well logging operations in wellbores) and/or seismic data (obtained from seismic operations) are obtained from underground earth formations, the data inherently containing information relating to the quantity or degree of underground deposits of hydrocarbons in the earth formations. Computer workstations in conjunction with software stored therein are used to process and interpret the data. The workstations include a processor, a memory for storing interpretation software, and an interactive display screen. The workstation will receive the well log or seismic data and, when the interpretation software stored in the workstation memory is executed by the processor, the workstation will interpret the data and display a novel set of results on the display screen. The set of results will include a novel visual display for viewing by an operator. The display may, for example, reveal the degree or quantity or type of underground deposits of hydrocarbons (e.g., oil) in the earth formation. One such novel set of results displayed on the workstation display screen is known as a “crossplot” and a “class data set”. A class data set represents a top view of a subsurface in an earth formation, the top view of the subsurface including, for example, a plurality of different earth formation classes where each class of the plurality of classes in the subsurface possesses a different set of characteristics. When the operator of the workstation views the class data set on the workstation display screen, the characteristics of each class of the subsurface being displayed can be determined.
In the seismic interpretation field, there is a strong need for such a class data set, since the class data set would assist the workstation operator to determine, for example, the type of and/or the existence of underground deposits of hydrocarbon in the earth formation.